The present invention relates to a memory card and a microcomputer with nonvolatile memory. More particularly, it relates to a technology which is effectively applied to a memory card equipped with a nonvolatile memory, such as flash memory (flash EEPROM) and a microcomputer with nonvolatile memory which is a combination of the nonvolatile memory and a microcomputer.
According to the present inventors' consideration, the following technologies are available with respect to memory card.
As external storage media for personal computers and portable devices, memory cards, such as MultiMediaCard (registered trademark) standardized by MMCA (MultiMediaCard Association), standardized by MMCA (MultiMediaCard Association), a standardization organization, have been widely known. The memory cards are used for recording still-frame images in digital video cameras, data in cellular phones, and pieces of music in music players and for other purposes. With respect to MultiMediaCard, for example, Non-patent Document 1 drawn up by MMCA lays down power supply specifications. According to the document, the power supply for MultiMediaCard is standardized as 1.8V system (1.65V≦Vcc≦1.95V) and 3.3V system (2.70V≦Vcc≦3.60V). At the same time the range of voltage between 1.95V and 2.70V (1.95V<Vcc<2.70V) is taken as inhibition region.
[Non-patent Document 1] MultiMediaCard System Specification Version 3.3